Field of Invention
The present invention relates broadly to cryptographic methods and devices. In some embodiments, it pertains to symmetric cryptographic methods and machines. Cryptographic devices and methods are generally used to encrypt and decrypt information transmitted through communication and transmission systems. For example, the cryptographic methods may be used to encrypt a phone call; in some embodiments, the phone call may be transmitted using voice over IP (internet protocol) using a mobile phone. These methods also may be used to encrypt passive data stored on a computer or another physical device such as a tape drive. Typically, the information is encrypted by a sending agent, sometimes called Bob, using his unique key(s), and the encrypted information, called ciphertext, is transmitted to a receiving agent, sometimes called Alice. Using her unique key(s), the receiving agent Alice applies a decryption device or method to the ciphertext. The output of this decryption device or method is the same information that the sending agent gathered before encrypting and sending it.